Because of their various characteristics, yeasts of the genus Schizosaccharomyces represented by Schizosaccharomyces pombe (hereinafter sometimes referred to as S. pombe) are considered as unicellular eukaryotes closer to higher animal cells and very useful yeasts as a host for expression of foreign structural genes, especially genes derived from higher animals. In particular, they are known to be suitable for expression of genes derived from animals such as human.
In order to express a protein utilizing transcription and translation systems of organisms, an expression cassette which comprises, upstream from a foreign structural gene encoding a heterologous protein, a promoter controlling transcription of the foreign structural gene, and a terminator to release mRNAs obtained by transcription, into a cell as a host cell. It is known that the expression efficiency is influenced by the type of the promotor used. It is possible to express a protein even without a terminator, and the terminator has not been considered important so far. However, in recent years, it is reported that the expression efficiency varies depending upon the type of the terminator used, in a budding yeast Saccharomyces cerevisiae (Non-Patent Document 1).